The present invention relates to an apparatus for feeding articles, preferably generally cylindrical articles. More particularly, this invention pertains to a method and an apparatus for feeding can bodies into a drawing press in which the action of the feeding mechanism is synchronized with the reciprocating action of the press.
The prior art teaches various methods and mechanisms for feeding cups into a redraw press. Common feeding devices include air transfer systems, walking beams and oscillating fingers. These devices act to advance a plurality of partially drawn cup shaped articles, sometimes called progression cups, from one drawing operation to another in a sequential can manufacturing system.
In order to feed progression cups into conversion dies or tooling in an integrated can manufacturing system, there are a number of limiting factors that must be addressed. A primary factor is that there is a limited time window in the redraw press cycle in which an incoming cup may be deposited within the open tooling. Unless the cup is precisely deposited, with regard to both time and position, damage will result to the cans and perhaps to the equipment.
Additionally, the contemporary can designs include cans which are not easily handled because of their lightweight, thin walls and oval configuration. Air transfer systems may not maintain the cup being transferred in its original condition, such as its round condition, within a die pocket destination. Also, air transfer systems do not guarantee positive control of cup transfer. Cam actuated transfer systems sometimes mar the exterior surface of a can being transferred.
The cup transfer system of this invention includes the use of a feed screw. Feed screws have been disclosed in the prior art to convey or control movement of articles, such as bottles, U.S. Pat. Nos. 3,026,991, 3,652,369 , and 3,866,753; cartridge shells, U.S. Pat. No. 2,387,638; pipes, U.S. Pat. No. 3,244,270; and container bodies, U.S. Pat. Nos. 3,635,069 and 3,650,374.
Despite progress in the area of feeding mechanisms, including the use of feed screws, there is still a need and a demand for positive feeding mechanisms such as those used to feed generally cylindrical cup shaped articles.
Accordingly, a new and improved apparatus for feeding progression cups into a drawing press is desired which links the feed system to the reciprocating action of the press and results in positive cup placement inside a tool pocket within the limited time window available.